Electric switch



(No Model.)

B. THOMSON.

ELEGTRIG SWITCH. No. 428,704. Patented May27, 1890.

WITNESSES: I 'INVENTOR I UNITED STATES PATENT Orrrcm HOUSTON ELECTL HC COMPANY, OF CONNECTICUT.

ELECTRIC SWITCH.

SPECIFICATION forming part of Letters Patent No. 428,704, dated May 27, 1890.

Application filed July 26, 1886. Serial No. 209,141. No model.)

To all whom it may concern.-

Be it known that I, ELIHU THOMSON, a citizen of the United States, and a resident of Lynn, in the county of Essex and State of Massachusetts, have invented a certain new and useful Electric Switch, of which the following is a specification.

My invention relates especially to electric switches, and has for its object the provision of a simple and cheap device wherein means are provided for securing or holding the switch closed and for giving an instantaneous rupture of the circuit when the switch is opened.

To attain the desired end my invention consists in a pivoted arm mounted upon a suitable base bearing one or more contacts, said arm being made of conducting material and'provided with a spring so arranged as to hold the switch open when desired or hold the operating-arm upon the dead-center when the switch is closed, all of which will be hereinafter first fully described, and then pointed out in the claims.

In the drawings, Figure 1 is a plan View of my improved switch, and Fig. 2 is a side elevation thereof. Fig. 3 is a plan of the same construction applied to a base having two contact-points for the switch-arm, and Fig. 4

is a side elevation of the last-named construction. Fig. 5 is a perspective view, and Fig. 6 a plan of the contact employed therewith.

Like letters of reference, wherever they occur, indicate corresponding points in all the figures.

A is the movable switch-arm, and H the operating-handle thereof.

G is the base-board whereon the parts are assembled.

Arm A is mounted upon a pivot P, its lateral movement being limited by a stop T. Suitable binding-posts for connection with the electrical conductors X Y are provided. One of said posts is connected to the contactspring B, with which arm A can make contact, and the other is suitably connected with the pivot of the switch-arm A, so that the circuit may be completed through the arm and contact.

to a curved piece C, secured by a pivot 19 to the switch-arm A. This spring, when the switch is closed by the arm A bearing upon contact B, acts upon a dead-point, the point of attachment of the springS to the basepiece G and the pivot P, as well as the pivot 19, being then in a substantially straight line, and the arm is held in this position. XVhen opened, as shown by the dotted lines in Fig. 1,

the spring S acts in such a manner that pivot p is drawn around, so that the spring'will act off the dead-point and throw the switch suddenly, so as to quickly rupture the circuit. In the position shown by dotted lines the spring holds the arm A against the stop T.

In the construction shown in Figs. 3 and 4 the arm A comes in contact with a fixed closing-spring B at each side of the pivot P, the binding-posts being connected with said contact-sprin gs. rectly to the arm A, the other extremity being secured at a pointopposite one of the contacts, as plainly illustrated in Fig. 3.

The operation of the switch is the same as above described,the spring acting upon a dead- 7 5 parts free from corrosion and insuring a good 8 5 electrical contact.

Having now fully described my invention, what I claim as new therein, and desire to secure by Letters Patent, is

1. The combination, with a pivoted switch- 90 arm A, of the two contact-springs B at opposite sides of the pivot, and a spring S, connected at one end directly to the switch-arm and at the other to a fixed support, as described and arranged, so as to exert a pull on 5 the switch-arm in line with the pivot and the contact-springs when the arm is turned to close the connection from one spring to the other.

The spring S is connected di- 50 S is a coiled spring attached, Figs. 1 and 2, 2. The combination, in an electric switch, I00

of a pivoted switcluarm A, having a handle Signed at Lynn, in the county of Essex and B attached to and carried thereby, and a State of Massachusetts, this 21st day of July, 10 spring" attached at one end to the switch-arm A. D. 1886. and at the other to a suitable support, and

5 applied, as described, so as to exert a pull across the pivotal point when the switch is \Vitnesses: closed and to one side thereof when the switch )l. L. THOMSON, is opened. 4120mm J. CARR.

ELII'IU THOMSON. 

